blower motor question

[Bob S]

This blower needs a new motor. The blower case is about 12"D, the fan itself is about 8"D.

The motor that was originally with it (now junk) was an AC/DC motor with a large (6"D) reostat. I want to mount a new motor and plan to control air blast with an air gate or similar.

Question is how big does the motor need to be and what speed motor would be best. I can get a 1100rpm (new surplus), 1/3 hp (I think) for $30.

Any opinions? Thanks.

Bob

[blksmth]

1/3 hp should be more than adequate for that size fan blade. The big blower sold by Centaur forge has a 1/5 hp motor at 3600 rpm, but it has a solid cast aluminum and balanced fan blade. 1100 rpm should not be too fast for the old riveted on fan blades like the one you have. One always has to wonder if the old fan blade will stand up to the rpm, but I have seen other old fans run by an 1100 rpm motor and it seemed to work OK. Give it a try and stand back when you first start it.

[John B]

Check the RPM on the old motor, and try to match it,

we have had touble in the past because the new motor fitted did not have enough speed(RPM) to give the output required.

[ArtWerkz]

Most off the shelf motors have a rpm of 1725. As blksmth mentioned the Centaur Forge model could be looked at. Also they have the air gates you may be wanting. Also if you are burning coke you will require more air. Things to consider. Let us know how you make out.

[bsiler]

I hope this isn't jumping in!
While this is being discussed I have a question.
I have a blower just like this one. It works very good with one problem.
The motor that on mine works good but leaks oil. When I put oil in the 2 fill holes it almost imediately runs out.
Is there a fix besides having the motor rebuilt. If not I may need to get a new motor also.

I also have the original reostat. On the slowest speed sometimes it is almost to much air. I think I need some type of air gate.

[pkrankow]

I hope this isn't jumping in!
While this is being discussed I have a question.
I have a blower just like this one. It works very good with one problem.
The motor that on mine works good but leaks oil. When I put oil in the 2 fill holes it almost imediately runs out.
Is there a fix besides having the motor rebuilt. If not I may need to get a new motor also.

I also have the original reostat. On the slowest speed sometimes it is almost to much air. I think I need some type of air gate.

Are there/were there felt wipers in those holes? They are just pads of felt to hold oil since electric motors require very little to operate properly.
Phil

[Bob S]

Thanks for all the replies....

I think I am going to keep looking for a higher speed (1725) motor. Horsepower is less of an issue. I think 1/4 hp would be plenty. I am planning on controlling the air to the fire with a slider that will go over the air intake.

The blades on this fan are not riveted on they are just twisted. I'm not too worried about it coming apart (but I do plan on standing off to the side when I first run it).

The old motor had no rpm or hp info on the plate. This picture (from another blower) is all there is.

The blower shown in this picture also leaks oil. I find that a few drops of a light oil keep it reasonably happy. So far anyway.

Thanks for the ideas. Bob

[Pat Roy]

IF you are re-using a fan you had in service, you should match the original speed. If you go slower it will not produce much air and if you go faster it will make considerably more noise and more pressure and volume. You may want to get a speed control in this case and/or possible a slide gate to control the flow. I use both because I have way too much blower.

[Sam Thompson]

I hope this isn't jumping in!
While this is being discussed I have a question.
I have a blower just like this one. It works very good with one problem.
The motor that on mine works good but leaks oil. When I put oil in the 2 fill holes it almost imediately runs out.
Is there a fix besides having the motor rebuilt. If not I may need to get a new motor also.

I also have the original reostat. On the slowest speed sometimes it is almost to much air. I think I need some type of air gate.

What type of bearings?

[Rob Browne]

My bit here would be. If the blower does not have bearings then be careful running it too fast and controlling the air blast with a gate. Much better to have the fan run slower and not wear out the bushes.

Cheers

[pkrankow]

My bit here would be. If the blower does not have bearings then be careful running it too fast and controlling the air blast with a gate. Much better to have the fan run slower and not wear out the bushes.

Cheers

so...air gate in the high side and/or a dump valve.

Phil

[HWooldridge]

I was fortunate many years ago to purchase a Buffalo forge with electric blower which had not seen any modifications after it left the factory. It has a 1/5 hp AC/DC motor with a sliding air gate between the blower and pot. The rheostat has 5 fixed positions and the paddle switch can be placed to touch two taps so I effectively have 9 speed settings. However, even at the lowest setting, the blast is much too strong for the average fire with the damper wide open - in fact, position 3 with no damper will generally blow fuel out of the pot. Even though they were installed on single forges, I believe most of these blowers were designed to support two or more forges so the blast could be left on all day with each smith working his own air gate as needed. Therefore, I'd say that most any conventional motor can be used with just an on/off switch while the air gate is used for air control and in your case, 1/4 to 1/3 hp at 1725 rpm ought to work fine. The most important thing is to use a centrifugal type to develop enough air pressure to push through the fire mass. Squirrel cage blowers are fine for gas forges but are not really suitable for solid fuel.

[bsiler]

pkrankow,
There is nothing in the holes. I kinda wondered about that myself.

Sam Thompson,
I hate to admit it but i'm not sure. I thought it would be bearings. It's old and possilbly the original motor, might be bushings?

Thanks for the questions
Billy

[Sam Thompson]

Bushes are bearings, just a bit simpler. Is there any play in them? If not I'd follow the instructions on the plate... You don't want to invalidate the guarantee :P

[pkrankow]

Bsiler,
If it is a bushing motor, there may have been felt wipers at some past time, but the motor was cleaned up aggressively removing the wipers. Wipers get dirty over time and look like a gross mess plugging the holes. Just get some thick felt padding, cut a square or rectangle and insert it edgewise into the hole till it *just* contacts the shaft It should hold itself into the hole nicely, and depending on the cap you may put a shoulder on it so there is more felt at the opening. Add oil to the felt, and the oil will slowly add oil to the bushing.

If it is anything other than bushings such as ball or roller bearings DO NOT ADD A WIPER!!! The bearings will catch and tear up the wiper and cause bearing failure!

Another possibility is that the motor was meant for light grease (or even heavy oil) and not light oil. In that case adding a wiper could also cause future problems as it will prevent adequate lubrication.

I hope I am more clear than mud now.

Phil

[Fe-Wood]

Could be like old British cars and motor cycles and have a "total loss oil system". Never change the oil, just add more :D

[bsiler]

Sam,
There doesn't seem be be any noticeable play.
Didn't think about the warranty.


pkrankow,
I think I did clean something out that I thought was dirt.
Is there a way to tell if it's bushings or ball bearings.
As you fellows can probably tell, I don't know much about electric motors.

I haven't used this blower but a couple of times. I have a Champion 400 that I use all the time.

Thanks for all the information,
Billy